1.     Effects of fertilizers on growth, yield and quality of different field crops, (cereals, legumes, oil seeds, forages, and industrial crops (roselle “Karkadeh”, sugar beet and guar) under irrigation.

2.     The response of field crops to fertilizers under rainfed conditions.

3.     The performance of crops in  legume/non-legume intercropping systems.

4.     The beneficial effects of organic fertilizers in saline soils.

5.     The interactions between fertilizers and other cultural practices (weeding, irrigation regime, plant density).